It is conventionally well known in the art that an oxidant derived from a color-forming developing agent and containing an aromatic primary amine couples with a color coupler when a silver halide color light sensitive material is treated in an image-wise exposure as well as color development, forming dyes, such as an indophenol, indoaniline, indamine, azomethine, phenoxyazine, phenazine and dyes similar to them, thus forming a dye image.
What is required for the dye image obtained in such a manner is that it does not show discoloration or color fading even if it is stored under high temperature and/or high humidity. Additionally, what is required for the non-colored portion in a silver halide light sensitive material (hereinafter referred to as color photographic material) is that it does not show yellow-stain (hereinafter referred to as Y-stain) due to light, heat or moisture.
However, in the case of a magenta coupler, the Y-stain in the non-colored portion due to light, heat or moisture as well as the color fading of the dye image portion due to light are extremely great, when compared to a yellow coupler or a cyan coupler, often causing troubles.
5-pyrazolones are widely used as couplers to form magenta dyes. It is a great disadvantage that dyes formed from 5-pyrazolo-5-ones have a secondary absorption in the range around 430 nm in addition to a primary absorption around 550 nm. Various researches were conducted in order to solve this disadvantage. A magenta coupler having anilino group in the third position of a 5-pyrazolone has a limited secondary absorption, mentioned above, and is advantageous in obtaining a printed color image. Such a method was disclosed, for example in U.S. Pat. No. 2343703 and UK Patent No. 1059994.
However, with the magenta coupler, mentioned above, a shelf stability is limited, and especially, a light resistance of a dye image was significantly poor, resulting in a disadvantageously great Y-stain in a non-colored portion.
In order to reduce the secondary absorption around 430 nm of the above-mentioned magenta couplers, the magenta colors shown in the following were proposed so as to provide a new measure: pyrazobenzimidazoles mentioned in U.K. Patent No. 1047612; indazolones mentioned in U.S. Pat. No. 3,770,447; 1H-pyrazolo[5,1-c]-1,2,4-triazole couplers disclosed in U.S. Pat. No. 3,725,067, UK Patent Nos. 1252418 and 1334515; 1H-pyrazol[5,1-c]-1,2,4-triazole couplers disclosed in U.S. Pat. No. 3,725,067, UK Patent Nos. 1252418 and 1334515: 1H-pyrazolo]1,5,-b]-1,2,4-triazole couplers disclosed in Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) No. 171956/1974 and Research Disclosure No. 24531; 1H-pyrazolo[1, 5,-c]-1,2,3-triazole couplers disclosed in Research Disclosure No. 24626; 1-H-imidazo[1,2,b-] pyrazole couplers disclosed in Japanese Patent O.P.I. Publication No. 162548/1984 and Research Disclosure No. 24531; 1H-imidazo[1,5,-b] pyrazole couplers disclosed in Japanese Patent O.P.I. Publication No. 43659/1985 and Research Disclosure No. 24230; 1H-pyrazolo[1,5,-d] tetrazole couplers disclosed in Japanese Patent O.P.I. Publication No. 33552/1985 and Research Disclosure No. 24220.
Among these examples, dyes formed from 1H-pyrazolo[5,1,-c]-1, 2,4-triazole couplers, 1H-pyrazolo[1,5,-b]-1,2,4-triazole couplers, 1H-pyrazolo[1,5,-c]-1,2,3-triazole couplers, 1H-imidazo[1,2,-b] pyrazole couplers, 1H-pyrazolo[1,5,-b]pyrazole couplers of 1H-pyrazolo[1,5,-d]tetrasole couplers have a significantly smaller secondary absorption around 430 nm of wavelength, when compared to the previously mentioned dyes formed from 5-1,2-pyrazolo-ones having an anilino group in the 3-position. This feature is very advantageous in regard to the color reproduction. Additionally, it is an advantage of such dyes that they show the significantly decreased Y-stain in the non-colored portion due to light, heat or moisture. However, azomethine dyes formed from the couplers, above, are extremely vulnerable to light. And worse, the above-mentioned dyes are easily discolored by light, significantly jeopardizing the performance of color photographic materials, especially color photographic materials for print. Consequently, such dyes have not been employed for a practical use.
In order to improve the light-resistance of magenta dye images formed from 1H-pyrazolo[5,2,-c]-1,2,4-triazole magenta couplers, a method was proposed in Japanese Patent O.P.I. Publication No. 125732/1974, where phenol compounds or phenyl ether compounds were added to 1H-pyrazolo[5,1,-c]-1,2,4-triazole magenta couplers.
However, it was revealed that such an art is not fully effective in preventing the magenta dye image, mentioned above, from fading, and that the prevention of the discoloration due to light was near-impossible.
In view of the disadvantages, above, the present invention has been developed. Therefore it is the first object of the invention to provide a color photographic material which features an excellent color reproducibility as well as a significantly improved light-resistance of a magenta dye image.
It is the second object of the invention to provide a color photographic material which features a magenta dye image where the discoloration due to light is minimized.
It is the third object of the invention to provide a color photographic material in which the generation of a Y-stain in a non-colored portion due to light, heat or moisture is prevented.